More men than women lost their jobs in the recession, making for some catchy terminology: “he-cession” has a lyrical ring to it. But, according to new research, some women are faring worse than others. Married mothers are experiencing a triple whammy: compared with married fathers, they’re experiencing more of a gap between jobs, they’re less likely to find a new job at all, and once they’ve secured a new paycheck, they earn considerably less. As it turns out, the “man-cession” may actually be a “mom-cession.”

“There does appear to be a motherhood penalty,” says study co-author Brian Serafini, a University of Washington doctoral candidate in sociology.

Moms are struggling longer to land a new position and earning less once they find one, even after controlling for education level and previous job and earnings histories. The research, to be presented Monday at the annual meeting of the American Sociological Association in Denver, Colo., sheds light on how having children can influence an employer’s opinion about a potential employee’s value.

When Serafini and his co-author, Michelle Maroto, an assistant professor of sociology at the University of Alberta, originally looked at broader categories of men and women in general, they found no gender difference in terms of how long it took people to find new employment. “We were suspicious,” says Serafini, who proceeded to further break down the groupings into single and married people and those with or without children. The researchers relied upon U.S. census data collected in 2004, 2006, 2008 and 2010 from the Displaced Workers Supplement, part of a monthly household survey.

The researchers were right to be skeptical: once kids entered the equation, conclusions changed considerably. “We found that the story is little bit more complicated,” says Serafini.

Married women with kids who lost their jobs between 2007 and 2009 had a 31% lower chance of finding a new job than married fathers with kids. But their alter-egos — single women without kids — were taking less time to find new jobs compared to similar men. In fact, single women who weren’t moms had a 29% greater chance than single men without kids of finding a new job.

The study didn’t examine the reasons behind the disparities, but Serafini has a pretty good idea what may be at play. “When making hiring decisions, employers have assumptions about mothers,” says Serafini. “There are stereotypes that they will be less productive employees because they will have to pick up their kids and leave work early.”

The funny thing is, research has found that moms are every bit as dedicated to their jobs as women without kids — or men, for that matter. In 2008, the Families and Work Institute’s National Study of the Changing Workforce found that women with and without children are equally ambitious. What women contribute to the family coffers is far from trivial, says Ellen Galinsky, the institute’s president. They are responsible for 45% of family income, with more than 1 in 4 women earning at least 10% more than their husbands.

“Despite these demographic changes, the results of this study indicate that stereotypes still appear to affect hiring decisions,” Galinsky wrote in an email. “Employers would do better to concentrate on talent — on who could do the best job — rather than make assumptions about men and women, which in this day are age are unlikely to be true.”

Married moms’ struggle to find a new job is even more striking considering that the current labor market appears more favorable to women, with vacancies in traditionally female-dominated service fields such as education and caregiving.

Pay inequities abound once women do find new jobs. Previous research has discovered that employees rejoining the workforce tend to net lower salaries, and the University of Washington findings bore that out. The study found that married moms in the 2010 survey earned $175 less each week than married fathers, which adds up to more than $9,000 a year.

It also concluded that married women without children were earning significantly less than their male counterparts. And single women with children were earning less than single men with children. But there was no significant difference between single men and women without kids and their reemployment earnings.

“When talking about the economic prospects for laid-off workers, we miss something when we just look at plain old sex differences,” says Serafini. “We speculate being a mother sends a signal to an employer that they may be less productive in the workplace.”

The solution? Dash the stereotype that it’s mom who’s solely responsible for kids’ care and feeding. The proportion of stay-at-home dads has doubled in the past decade, for example, though it’s still small at 3.4%.

“The more men engaged in caregiving and the more men who identify as primary caregivers, the more likely it will be that people won’t assume that women’s job performance will diminish because of her kids,” says Brad Harrington, executive director of the Center for Work & Family at Boston College. “People will realize it’s just as likely for men to make trade-offs and compromises. But that’s going to be a long time coming.”